def run(self):
"""Worker main method"""
self.worker = Worker()
for host in self.servers:
self.worker.add_server(host)
self.register_tasks(self.task_module)
# self.worker.work() blocks in libgearman.so,
# so make it time out occasionally and give back control.
self.worker.set_timeout(TIMEOUT)
while self.is_running: # is_running is always True
result = self.worker.work()
if result not in [GEARMAN_SUCCESS, GEARMAN_TIMEOUT]:
LOGGER.warn('Oilcan: Gearman task result code: %d', result)
class OilcanWorker(Process):
"""Runs in a sub-process. There can be lots of these.
Listens for Gearman messages and runs tasks.
"""
def __init__(self, task_module, servers):
super(OilcanWorker, self).__init__()
self.task_module = task_module
self.servers = servers
self.is_running = True
self.worker = None
self.task_map = {}
def run(self):
"""Worker main method"""
self.worker = Worker()
for host in self.servers:
self.worker.add_server(host)
self.register_tasks(self.task_module)
# self.worker.work() blocks in libgearman.so,
# so make it time out occasionally and give back control.
self.worker.set_timeout(TIMEOUT)
while self.is_running: # is_running is always True
result = self.worker.work()
if result not in [GEARMAN_SUCCESS, GEARMAN_TIMEOUT]:
LOGGER.warn('Oilcan: Gearman task result code: %d', result)
def register_tasks(self, task_module):
"""Inspect task_module and records the tasks it finds.
Tasks are a function with an is_oilcan_task attribute.
Usually this attribute is set via the @tasks decorator.
"""
system_import(task_module)
tasks = sys.modules[task_module]
LOGGER.debug('Oilcan: Imported: %s', tasks)
for name in dir(tasks):
if name.startswith('__'):
continue
func = getattr(tasks, name)
if hasattr(func, 'is_oilcan_task'):
self.task_map[name] = func
self.worker.add_function(name, self.run_task)
LOGGER.debug('Oilcan: Registered task "%s"', name)
if not self.task_map:
LOGGER.error('Oilcan: No tasks found in module "%s"',
self.task_module)
return
def run_task(self, job):
"""Called by Gearman"""
func = self.task_map[job.function_name()]
workload = job.get_workload()
func_log = '%s(%s)' % (func.__name__, workload)
LOGGER.debug('Oilcan: Running task: %s', func_log)
ret = None
try:
ret = func(workload)
except Exception: # pylint: disable-msg=W0703
job.send_fail()
LOGGER.exception('Exception calling %s', func_log)
# Gearman tasks must return a string result
return "OK" if not ret else str(ret)
